The invention relates to an operating room light with ceiling suspension and at least one swivel arm through which electric conductors are routed, the said swivel arm being mounted on and rotatable around a shaft protruding from the ceiling and containing internal electric conductors, while slip rings electrically insulated from each other are disposed on the shaft in the region of its external face for the purpose of making electrical connections by means of slip ring pickups, which maintain contact by spring pressure and are housed inside a sleeve-like swivel-arm head constituting part of a rotary joint.
From DE-PS 11 93 897 there is known an operating room light with a swivel arm which is disposed on and is axially rotatable around a pivot protruding from the ceiling, the pivot being formed as a supply post through which not only electrical power but also oxygen and nitrous oxide are routed to a connection head, from which the most diverse instruments needed for the operation can be supplied. The pivot consists of a hollow pipe with attached rotary joint, which is provided with slip rings for transmission of electrical current between support arm and pivot; this is a relatively complex arrangement, since the rotary joint is assembled from a large number of individual elements such as rotary ring, spacer ring, intermediate rings, ring nut, spring rings and cams; thus it is particularly problematic, in view of the complex structure, to provide a stock of such rotary joints for modular assembly of operating room lights for various applications.
Furthermore, from DE-GM 89 13 757 [German Utility Model] there is known a video transmission system in operating room lights which describes an operating room light construction and a camera system with cable lines for transmission of video and control signals for a camera mounted in the light, the cable lines being routed internally through the operating room light suspension and slip rings for transmission of high-frequency video and control signals of a camera being provided.
This is a relatively complex structure, in which a plurality of individual segments with high assembly and adjustment expense must be used; even subsequent addition of swivellable booms proves to be problematic, since individual adaptations are necessary for the purpose.
Furthermore, from DE 40 04 648 C2 there is known a system for attachment of reflector lights to ceiling and wall surfaces, in which a connection block constituting a hollow body and a light base are provided with connecting means that can be inserted interlockingly in the connection block; the underside of the connection block is formed as a hollow-body bottom with sliding surface to permit rotary movement of the light base, and a light-base flange that can be inserted in the seating groove is used as the interlocking connecting means. A slip ring arrangement for current transmission is not provided, and so the horizontal swivelling capability lies in the angular range of about 360.degree..
From U.S. Pat. No. 5,379,205 there is known a swivellable holding device for a wall light, in which a first and a second swivel arm are provided with recesses for routing electrical cables; the swivelling range is restricted in this case also.
Furthermore, from DE 42 10 649 A1 there is known a device with a rotary arm for lighting the interior of furniture items from the outside; between the rotary arm and a support body there are provided actuating means for the electrical supply of the light source disposed at the end of the rotary arm, so that current flows as soon as the rotary arm is positioned outside the furniture item, whereas the current supply is interrupted when the rotary arm is positioned inside the furniture item.